Neoteny/paedomorphosis in C. orientalis

[caleb]

Has anyone seen neoteny/paedomorphosis in captive C. orientalis? I have a year old gilled individual that's well over 4 cm. It's had a yellow belly for a couple of months now, but no sign of losing its gills as yet...

 

[Azhael]

I´ve never heard of neoteny in H.orientalis, the closest was a case (posted here) about a neotenic C.ensicauda.
I find that morphing time varies wildly among my larvae. Some individuals morph tiny and the whole process happens very fast, but others retain the gills even when the body shape and coloration are typically juvenile (and they grow larger too, obviously). These usually reabsorb the gills slowlier, and even linger on in the water when they only have stubs left. Maybe that´s something like what you are seeing? My largest morph ever was about 4,5 cm long...

I guess it could be seen as some degree of facultative neoteny, but in my experience, even the larger morphs are very far from maturity at the time of morphing, so it´s hardly neoteny, it´s more like sheer laziness to morph xD

 

[caleb]

Yes, I saw the posts on the ensicauda, that seemed a particularly bizarre individual.

Interesting to hear that the shape & colouration can appear some time before metamorphosis. I'm more used to Triturus, Lissotriton, & Ichthyosaura, where metamorphosis is usually very rapid after the juvenile colouration appears.

I think I might be able to beat your 4.5cm if it can hang on a few weeks more...

 

[Yahilles]

I had some orientalis larvae that hatched at latest in July 2010 and morphed in February 2011, so i think i could call that neoteny, though they just looked like larvae in middle stage (four legs, backfin and water-skin), not like morphs that retained gills.

 

[Azhael]

As it happens i have a "morph" that illustrates exactly what i was refering to earlier, so i thought i´d try to take a couple of pictures. This individual has been like that for about three weeks already and still refuses land. Despite the terrible quality of the pics, i think you can see the stubs of the gills, the completely developed skin coloration and even the clearly juvenile shape of the body and head. This kind of prolonged metamorphosis is the closest thing to neoteny in this species i ever heard of.

 

[Yahilles]

I had my C. ensicauda larvae looking similar when i raised them in pondtype tanks last year:

but they finally left the water.

 

[Joost]

I had a cyanurus just like Azhael's orientalis. It stayed aquatic and the gills didn't disappear for months.
After some 5-6 months the gills disappeared at last, but the juvenile is still kept aquatic, with it's parents. I didn't make pictures at that time unfortunately.

 

[caleb]

As it happens i have a "morph" that illustrates exactly what i was refering to earlier

Yes, that's almost exactly what mine looks like. Its gills have reduced a lot over the weekend, and it's poking its head out of the water now, so I guess it is going to metamorphose. It's just short of 45mm.